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Obesity suppresses parts of the brain responsible for volitional effort
Last reviewed: 23.04.2024
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A new study of scientists from the Yale University (USA) showed the influence of the brain on a strong-willed effort to lose weight in people with excess weight.
Predisposed to obesity, a person who is trying to lose weight, can face resistance to his own brain. Scientists say that this category of people breaks the "glucose meter" in the brain. In this state, there is a suppression of the will center in the cortex, which leads to an unrestrained desire to eat.
Normally, eating leads to an increase in blood glucose, which is a signal to the brain and blocks the work of a food reinforcement center, which leads to a sense of satisfaction from eating. In people with excess weight, the brain reinforcement center does not react to the level of glucose in the blood, and, unfortunately, does not turn off.
The study involved 9 people with normal body weight and 5 - with overweight. All participants were shown pictures of food (French fries, cauliflower, salad and ice-cream). People had to assess their hunger, and also, the quantity and the products that they would like to eat. A few hours after eating, the test was repeated.
But this time, some participants artificially lowered the glucose level from the background indicator (9 mg / l) to 7 mg / l by the introduction of insulin. As a result, the subjects began to feel hungry, and they wanted to eat high-calorie food. The study of the brain with MRI showed an increase in the activity of the islet zone and the striped body, which are responsible for the feeling of saturation and satisfaction from eating. The volitional center of the cerebral cortex, responsible for making decisions, is not superfluous, was sharply suppressed.
The obtained results show that the sensitivity of the brain zones responsible for a sense of satisfaction with food in people with obesity is reduced for unknown reasons, which leads to the desire to eat, regardless of the amount eaten.